In an air-conditioning system of the related art, one or more outdoor units and one or more indoor units are connected to each other with pipes so as to constitute a refrigerant circuit in which a refrigerant circulates such that a vapor compression refrigeration cycle is performed.
Indoor air conditioning may be performed by carrying out temperature control or by carrying out humidity control. There has been proposed a system that processes temperature control and humidity control separately so as to increase a refrigerant evaporating temperature in a refrigerant circuit of the temperature control side, and thereby reduce power consumption (see Patent Literature 1, for example).
A humidity control device of this system has a refrigerant circuit, which is provided separately from that of an air-conditioning device, and serves as a ventilation device so as to perform humidity control with a high-efficiency refrigeration cycle using the outdoor air.